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[en] The authors are conducting an imaging survey of pairs of elliptical galaxies. Some pairs present a common pattern of distortion interpreted in terms of tidal effects other examples share the same morphology. Characteristics of 24 new systems are listed. The authors' pairs are drawn from a sample of binary and multiple galaxies which has in turn been extracted from the CGCG, UGC (Nilson, 1973) and VV (Vorontsov-Velyaminov, 1959) catalogues. This sample includes that of Karachentsev (1972). It contains 1800 pairs, among which 700 are S - S or mixed morphology pairs. The authors are working on the remainder to produce a sample of close physical pairs of elliptical galaxies. One of the interests of this work is to provide a sample selected on purely optical criteria. This will allow statistical studies of non-optical properties of these pairs (in particular radio emission). The authors have so far obtained charge-coupled device (CCD) images of 125 pairs with a 2m telescope and velocities' differences of 78 pairs were obtained using the 1.93 meter telescope of Observatoire de Haute Provence and from the literature. One is an optical pair (VV 190). Eighteen of our pairs present the morphological effect described in Davoust and Prugniel (1988): the external parts of each member are stretched in opposite senses in a direction rougly perpendicular to the pair axis. The proportion of 15 plus or minus 4 percent distorted pairs confirms previous estimates
[en] The diameters d/sub r/ of inner ring structures in disk galaxies are used as geometric distance indicators to derive the distances of 453 spiral and lenticular galaxies, mainly in the distance interval 4<δ<63 Mpc. The diameters are weighted means from the catalogs to Kormendy, Pedreros and Madore, and the authors. The distances are calculated by means of the two- and three-parameter formulae of Paper II; the adopted mean distance moduli μ0(r) have mean errors from all sources of 0.6--0.7 mag for the well-observed galaxies
[en] The author analyzed the morphologic changes of bone structures from 1256 radiographs of 314 patients with temporomandibular joint arthrosis, which were obtained by the oblique-lateral projection and orthopantomography. The interrelations of the bone changes and clinical symptoms were examined. Also, the positional relationships of condylar head, articular fossa and articular eminence in the mouth open and closed state were observed in the patients with bone changes. The results were as follows; 1. The most frequent bone change in the TMJ arthrosis was eburnation of cortical bone (35.64%) of total cases. Then came bone surface erosion and localized radiolucency (26.18%), marginal proliferation (9.7%) and flattening of articular surface (9.58%) in that order. 2. The most frequent site of bone change was articular eminence (41.70%). The came condylar head (21.09%) and articular fossa (20.73%) in that order. 3. In the patients with bone changes, their clinical symptoms were pain (51.55%), clicking sound during mandibular movement (37.71%) and limited mandibular movement (10.73%). In the patients complaining pain, their radiographs showed eburnation of cortical bone (30.68%), bone surface erosion and localized radiolucency (27.45%) and flattening in the (30.68%), bone surface erosion and localized radiolucency (27.45%) and flattening of articular surface (10.68%). 4. The condylar positional changes in the TMJ arthrosis patients with bone changes were as follows: in the mouth closed state, there were the widening of joint space in 624 cases (50.00%), the narrowing of joint space in 543 cases (43.47%) and bone on bone relationships in 82 cases (6.57%). In the mouth open state, there were forward positioning of the condyle in 332 cases (28.55%), limitation of movement in 332 cases (28.55%), bone on bone relationships in 248 cases (21.31%) and downward positioning of condyle in 217 cases (18.66%). Bone on bone relationships in 248 cases (21.32%) and downward positioning of condyle in 217 cases (18.66%). 5. In the TMJ arthrosis patients with bone changes, 1249 cases of abnormal condylar position in the mouth closed state and 1163 cases of abnormal condylar position in the mouth open state could be interpreted. so, for the radiographic interpretation of TMJ arthrosis, the reading of condylar positional changes as well as that of bond changes should be preformed and their interrelations should be profoundly considered.
[en] Detailed macro- and microscopic analysis of spatangoid echinoid, Heteraster renngarteni Poretzkaja showed a remarkable variation in morphology and alternation of short and long pores in the frontal ambulacrum. The differentiation of pores in the frontal ambulacrum has been interpreted as an adaptive strategy for survival in a shallow shelf environment whereas, variation in morphology appears to be influenced mainly by grain size of the substrate. (author)
[en] The purpose of this study is to detect morphological changes of the maxilla following the operation of paranasal sinuses in the orthopantomogram. 1) The measurement of the angle set up by two reference lines which represent posterior aspect of the maxilla and skull base was made. 2) The mean angle in the post-operative patients showed significantly smaller than that in the normal subjects. 3) The forms of posterior aspect of maxilla were classified into 5 types. (flat, convex, concave, uneven and obliterated.) 4) In contrast with the convex type in the majority of normal subjects, approximately half of the post-operative patients showed the concave type. 5) These results may suggest that the superior part of the posterior aspect of the maxilla tend to depress following the operation of these paranasal sinuses.
[en] Determining the structural origins of amyloid fibrillation is essential for understanding both the pathology of amyloidosis and the rational design of inhibitors to prevent or reverse amyloid formation. In this work, the decisive roles of peptide structures on amyloid self-assembly and morphological diversity were investigated by the design of eight amyloidogenic peptides derived from islet amyloid polypeptide. Among the segments, two distinct morphologies were highlighted in the form of twisted and planar (untwisted) ribbons with varied diameters, thicknesses, and lengths. In particular, transformation of amyloid fibrils from twisted ribbons into untwisted structures was triggered by substitution of the C-terminal serine with threonine, where the side chain methyl group was responsible for the distinct morphological change. This effect was confirmed following serine substitution with alanine and valine and was ascribed to the restriction of intersheet torsional strain through the increased hydrophobic interactions and hydrogen bonding. We also studied the variation of fibril morphology (i.e., association and helicity) and peptide aggregation propensity by increasing the hydrophobicity of the peptide side group, capping the N-terminus, and extending sequence length. Lastly, we anticipate that our insights into sequence-dependent fibrillation and morphological diversity will shed light on the structural interpretation of amyloidogenesis and development of structure-specific imaging agents and aggregation inhibitors.
[en] VLBI observations were made on 15 March 1981 at 13 cm of the images of the twin quasar 0957 + 56A,B. These observations probed the milliarcsecond (mas) structure of the twin quasar and its angular environs, with submilli-Jansky sensitivities. These observations yielded the first detailed studies of images from a gravitational lens, confirming the existence of the phenomenon on cosmic scales. The main results include the following: (1) the brightness distribution of images A and B can be related with a linear transformation; (2) any other compact radio images must be less than 1/30 the intensity of image B; (3) the extended (arcsecond) jet found in image A does not appear in image B; (4) a time delay between the two images may be apparent when the A and B cores are compared with A following B; (5) a compact, weak radio source, G, exists at the position of the center of the cD galaxy believed to be part of the lens and is likely to be its radio core; and (6) the relative positions of G, B, A have been found with statistical errors of less than a mas, with positions (G = (0,0)) of A-G = (1071,5018), and B-G = (-181,-1029) mas. The A and B images reveal the source to be a typical radio quasar, with a one-sided jet which extends to its core
[en] A new determination of the SN-frequency in different morphological types of galaxies, obtained from the material of the Asiago SN-Search, is presented. From these values the authors derive a mean interval between SN events in our galaxy consistent with values determined in different ways
[en] The linear diameters D/sub r/ of the inner ring (r) and pseudo-ring (rs) structures in spiral galaxies of different morphology types and stage Sab to Sd (2< or =T< or =7) in the revised Hubble system are calibrated by means of approx.150 galaxies which have the best determined distance moduli μ/sup w/0(Λ/sub c/) and μ/sup w/0(V/sub M/) previously derived from tertiary indicators (B0/sub T/, D0) via the corrected luminosity index Λ/sub c/ and from the 21 cm line widths via revised versions of the Tully-Fisher relations